1. Marker Board Review You should have a marker board, a marker, and a paper towel to erase! Ready??? GO!!!

2. #1 - A balloon is filled with 3 gases: nitrogen, oxygen, and hydrogen. The total pressure of the gases is 8.51 atm. If the partial pressure of nitrogen is 3.84 atm, and the partial pressure of oxygen is 2.20 atm, calculate the partial pressure of hydrogen.

3. Answer: Partial pressure of hydrogen = 2.47 atm

4. #2 - A sample of gas is 7.89 L at 293 K. How many degrees must the temperature decrease to change the volume to 6.00 L?

5. Answer: 70 K It will change from 293 K to 223 K, which is a difference of 70 K.

6. #3 - A piston filled with oxygen gas has a pressure of 240.0 mm Hg at 225 mL. If the pressure is decreased to 0.150 atm, what will be the new volume of the gas?

7. Answer: 474 mL Don’t forget to change P1 to atm!

8. #4 - A sample of gas at 150.0 K has a pressure of 900.0 mm Hg. It is cooled until the pressure reads 700.0 mm Hg. What is the new temperature in both Kelvin and degrees Celsius?

9. Answer: 116.7 K and -156.3 o C

10. #5 - A 250.0 mL oxygen sample is measured at 25.0 o C and 720.0 mm Hg. How many moles is this?

11. Answer: 0.00968 moles O 2

12. #6 – 560.0 mL of nitrogen are measured at 28.0 o C and 1.50 atm. Calculate the volume under STP.

13. Answer: 762 mL

14. #7 - Determine how many liters 8.80 g carbon dioxide gas would occupy at STP.

15. Answer: 4.48 L